Process for improving color develop-ability of reversal photographic films

ABSTRACT

THERE IS PROVIDED AN IMPROVEMENT IN THE CONVENTIONAL REVERSAL COLOR PROCESS, WHEREIN A PHOTOGRAPHIC ELEMENT CONTAINING THREE PHOTOGRAPHIC SILVER HALIDE EMULSION LAYERS IS SUBJECTED TO (1) A FIRST EXPOSURE TO PRODUCE A LATENT IMAGE, (2) DEVELOPMENT IN A PHOTOGRAPHIC DEVELOPER FOR PRODUCING A BLACK-AND-WHITE NEGATIVE IMAGE, (3) EXPOSURE TO LIGHT OF A COLOR TO WHICH SAID FIRST EXPOSED SILVER HALIDE EMULSION LAYER IS SENSITIVE, AND (4) A SECOND DEVELOPMENT IN A COLOR DEVELOPER CONTAINING AN AROMATIC PRIMARY AMINE COLOR DEVELOPER CONTAINFOR PRODUCING A COLORED IMA AMINE COLOR DEVELOPING AGENT AND A PHOTOGRAPHIC COLOR COUPLER SELECTED FROM THE GROUP CONSISTING OF A MAGENTA FORMING PYRAZOLONE COLOR COUPLER, A CYAN FORMING PHENOLIC COUPLER, AND A YELLOW FORMING OPEN CHAIN KETOMETHYLENE COLOR COUPLER, THE IMPROVEMENT COMPRISING PROVIDING AS A BINDER FOR SAID SILVER HALIDE, GELATIN AND A SPECIFIC WATER-SOLUBLE COPOLYMER EXHIBITING A MOLECULAR WEIGHT OF FROM 5,000 TO 3,000,000 AND FURTHER CONTAINING A SPECIFIC REPEATING UNIT WITHIN ITS MOLECULAR STRUCTURE.

United States Patent US. Cl. 96-22 8 Claims ABSTRACT OF DISCLOSURE There is provided an improvement in the conventional reversal color process, wherein a photographic element containing three photographic silver halide emulsion layers is subjected to (l) a first exposure to produce a latent image, (2) development in a photographic developer for producing a black-and-White negative image, (3) exposure to light of a color to which said first exposed silver halide emulsion layer is sensitive, and (4) a second development in a color developer for producing a colored image, said color developer containing an aromatic primary amine color developing agent and a photographic color coupler selected from the group consisting of a magenta forming pyrazolone color coupler, a cyan forming phenolic coupler, and a yellow forming open chain ketomethylene color coupler, the improvement comprising providing as a binder for said silver halide, gelatin and a specific water-soluble copolymer exhibiting a molecular weight of from 5,000 to 3,000,000 and further containing a specific repeating unit within its molecular structure.

BACKGROUND OF THE INVENTION (1) Field of the invention The present invention concerns a color development of a coupler-free type reversal multilayer color photographic sensitive material and especially to a process for increasing an amount of dye produced in reversal color images.

(2) Description of the prior art In the multilayer color photographic sensitive material containing a blue sensitive emulsion layer, a green sensitive emulsion layer and a red sensitive emulsion layer on a support, there are a coupler-containing type color sensitive material which contains silver halide and color formers (hereinafter it is called as coupler) which form dyes by reacting with an oxidation product of an aromatic amine photographic developing agent in the photographic emulsion layers and a coupler-free type color sensitive material which does not contain couplers in the photographic emulsion layers (the coupler is included in the color developing solution). The present invention relates to such coupler-free type color sensitive material.

In the coupler-free color sensitive material, the following treatments are usually practiced in turn after exposing to light, that is, monochromatic white-black development, exposing to a red light at a support side of the sensitive material, cyan color development by a cyan color developer containing a cyan coupler and an aromatic amine photographic developing agent, exposing to a violet light at an emulsion side, yellow development by a yellow color developer containing a yellow coupler and an aromatic amine photographic developing agent, and magenta color development by a magenta color developer contain- 7 3,745,007 Patented July 10, 1973 ice SUMMARY OF THE INVENTION Detailed description of the invention The present invention concerns a new process for improving the density of reversal color images in the cyan color development, yellow color development and magenta color development, and especially to a new process for improving the density of magenta color images. According to the present invention, it is possible to obtain a more efiicient color reproduction system and to produce a thinner emulsion layer by increasing the density obtained in the reversal color images. Accordingly, it is possible to improve sharpness and to econimize silver halide in the emulsion layer.

The new process for improving the density of the reversal color images by the present invention comprises treating a silver halide gelatin emulsion containing the following water soluble polymer as the binder with color developer containing color couplers. The water soluble polymers used for the above-mentioned object, which have been found out by'these inventors, are those having a repeated unit structure represented by the following formula:

R2 latnltoflta R hydrogen atom or methyl group R hydrogen atom or methyl group R hydrogen atom or lower alkyl group (1-4 carbon atoms) X is a range of x 210 which represents a ratio of both blocks represented by the above-mentioned rational formula. When x: 100, it represents polyacrylarnide.

wherein Especially preferable polymers among these polymers are those having a number average molecular weight in a range of SWIG-3,000,000. (Abbreviated as n.a.m.w.)

In the following, water soluble polymers used are shown, as exemplary, and not as limiting.

(l) Polyacrylamide (preferably l0,0003,000,000 in n.a.m.w.)

(2) Acrylamide-acrylic acid copolymer (preferably 10,000l,000,000 in n.a.m.w.)

(3) Acrylamide-methacrylic acid copolymer (preferably 10,000l,000,000 in n.a.m.w.)

\ hours) icon)-x (4) Methacrylamide-acrylic acid copolymer (preferably 10,000-200,000 in n.a.m.w.)

(5) Methacrylamide-rnethacryliccopolymer (preferably 10,000-200,000 in n.a.m.w.)

(6) Methacrylamide-ethyl methacrylate copolymer (preferably 10,000-200,000 in n.a.m.w.)

CH: CH:

As to the range of X is greater or equal 75 and smaller or equal 95 concerning from water soluble polymers 2 to 6.

The water soluble polymer used in the present invention may be added solely to a gelatin emulsion or may be added by substituting a part of gelatin in the emulsion. Though addition of the water soluble polymer may take place at any step before coating of the emulsion, it is preferable to add at the step from afterripening to coating. A preferable amount is in a range of 1%90% particularly 50% (by weight) based on the combined amount (weight) of said gelatin and said copolymer.

According to this invention, good results are obtainable in the gelatin emulsion that contains silver bromoidodide as the silver halide. But it is possible to apply the present invention to many kinds of another silver halide-gelatin emulsions. The silver halide emulsion may be sensitized by compounds which contain labili sulfur such as sodium thiosulfate and allyl thiourea etc., and/or complex salts of monovalent 'gold and thiocyanic acid, and/ or reduction sensitizers such as amino compounds and stannous chloride (refer to The Theory of the Photographic Process: 3rd edition; McMillan Company, New York (1966), pages 113- 116), and/or polyalkylene oxide derivatives. In order to give green sensitivity and red sensitivity, the emulsion may include sensitizing dyes which sensitize a wavelength range of 500-700 me, for example, 1,1'-diethyl-2,2'-cyanine iodide and 3,3'-diethy1-9-methyl carbocyanine iodide (refer to the above-mentioned literature, pages 199-232). The emulsion may include stabilizers such as 4-hydroxy-6- methyl-l,3,3a,7-tetrazaindene (refer to the same literature, pages 344-346), hardeners such as formaldehyde and mucobromic acid (refer to the same literature, pages 54- 60) and a wetting agents such as saponin and sodium alkylbenzene sulfonate.

Development of the multilayer color photographic material containing silver halide gelatin emulsions which contain a water soluble polymer is carried out by a common reversal color precessing for the coupler-free type sensitive material. Namely, at least a color developing agent and a dilfusible coupler for cyan, magenta or yellow are included in each color developer. As the color developing agent, there are used well-known paraphenylenediarnine derivatives such as 4amino-N,N-diethyl-aniline, 4-amino- N,N-diethyl-3-methylaniline, 4-amino-3-methyl-N-methyl- N (B methylsulfoanmidoethyDaniline and 4-amino-3- methyl-N-ethyl-NQfi-hydroxyethyl) aniline, etc. (refer to the above mentioned literature, page 387). As the diffusible cyan coupler, there are used well-known phenolic couplers such as 2 chloro-l naphthol, 2,4-dichloro-lnaphthol, 2,4-dichloro 1 naphthol, 2(O-acetamido-flphenethyl)-1-hydroxy naphthamide, etc. (refer to the above-mentioned literature, page 387). As the difiusible magenta coupler, there are used open-chain methylene type couplers such as amylacetonitrile, 2-cyanoethyl benzofuran and benzylacetonitrile and cyclic methylene coupler such as l-phenyl-3-(4-chlorobenzamido)-5-pyrazo1one, 1- phenyl-3-(3-nitrobenzoylamino) 5 pyrazolone and l- (2,4,6-trichlorophenyD-3-(4-nitroanilino)-5-pyrazolone.

As the difiusible yellow coupler, there are used acylacetamide type open-chain methylene couplers such as 2-acetanilide, 2-aceto-2',4'-dichloroacetanilide, 2-benzoylacetanilide, 2-benzoyl-2'-methoxyacetanilide and 2-methyl-4- (methyl sulfonamidoethyl)ethylaniline, etc. (refer to the above-mentioned literature, page 389 and G. H. Brown et al., Journal of the American Chemical Society, 79 pages 2917-2927 (1957). These well-known color developing agents and couplers are used in combination.

A better understanding of the present invention will be gathered from the following examples, which are merely illustrative and not limitative of the present invention.

EXAMPLE 1 After melting by heating a high-sensitive gelatino silver bromoiodide reversal color emulsion which was sulfursensitized and gold-sensitized (content of silver iodide: 3.5% by mol), it was wetted to a cellulose triacetate film base. Couplers were not included in the emulsion.

The binder of the silver bromoiodide in the coated emulsion was gelatin which contained polyacrylamide (molecular weight: 3,000,000, and molecular weight: 490,000) in many ratios. This emulsion layer was exposed to light by using a NSG II type sensitometer and processed to the following treatments.

0. Minutes 1 Prehardner bath 27 1 2 Water was 27 1 3 Black and white 27 4 4 Water wash 27 3 Reversal exposure to white light.

6 Magenta development 27 5 7 Water wash 27 2 8 Fix 27 3 9 Drying (sample taken for silver anal 10 Ferricyanide bleach 27 5 11 Fix 27 3 12 Water wash and drying (sample taken for color density measurement).

The various processing solutions has essentially the following compositions:

Prehardener bath:

Sulfuric acid (cone) cc 1.7 Borax (10 hydrate) g 20 Potassium bromide g 2.3 Sodium sulfate g 200 37% formaldehyde ..cc 10 Sodium bisulfiate g.. 1 Water to make litr 1 Black and white developer:

N-methyl-p-aminophenol sulfate g.. 5 Anhydrous sodium sulfite g 79 Hydroquinone g 2 Sodium carbonate (monohydrate) g 40 Potassium bromide g-.. 3.5 Potassium thiocyanate g.. 20 0.1% potassium iodide cc 12.5 Sodium hydroxide ..g 1.0 Water to make -litre l Magenta developer:

Sodium sulfite 5.0 4 amino 3 methy1-N,N-diethylaniline hydrochloride g-.. 2.0 1 phenyl 3 (3-nitrobenzoylamino)-5-pyrazolone g 1.4 Sodium hydroxide g 2.5 n-Butylamine cc 5 Water to make ..litre 1 Ferricyanide bleach:

Ferricyanide g 60 Potassium bromide g 20 Water to make litre.. 1 Fix:

Sodium thiosulfate g Sodium sulfite Q 15 Water to make litre 1 A ratio (by weight) of silver bromoiodide to the binder in the emulsion was 5 g. of binder (gelatin 100% by weight)/1l g. of silver bromoiodide. Data are shown in Table 1 in which gelatin of the binder is substituted by polyacrylamide in various ratios.

TABLE 1 Silver Ratio of polymer in developed binder of gelatinby color Magenta polymer mixture Magenta developer, max- (percent by weight) D mg. Ag/10 cm. silver 7 a 1. i 1. 9 8. 0.23 16 a olyacrylarni 0 mo ecu ar weight 3,000,000 2. 1 s. 2 0. 20 (polyacrylamide, molecular weight 3,000,000) 2. 3 8. 6 0. 27 10% (polyacrylarnide, molecular weight 490,000) 2. 3 8. 7 0. 20 40% (polyacrylamide, molecular weight 490,000) 2. 4 8. 9 0. 27

Increase of -20% or so of D /amount of silver was recognized when adding the polyacrylamide of the present invention as compared with no addition thereof.

EXAMPLE 2 The same procedure was carried out as in Example 1 but using acrylamide-acrylic acid copolymer. 4 kinds of acrylamide-acrylic acid copolymer having approximately 100,000 of molecular Weight in which x:(l00-x)=90:10, 70:30, 50:50 and 30:70 and 4 kinds of said copolymer having approximately 2,000,000, 1,300,000, 700,000 and 100,000 of molecular weight in which x: (100-x) =70130 were used.

Data are shown in Table 2.

TABLE 2 Silver Ratio of polymer in developed binder of gelatinby color Magenta polymer mixture Magenta developer, 1 (percent by weight) Dmnxu mg. Ag/lO cm: silver 0% 1. 8 8. 3 0. 22 16% M.W. 100,000 :0: (100-Z) =90: 10.- 2. 0 8. 0 0. 25 16% M.W. 100,000 I: (100 1t) 70:30-. 1.9 7. 0 0. 27 16% M.W. 100,000 I: (100-:r) =50:50 2. 5 8. 7 0. 29 16% MW. 100,0002: (100z)=30:70 2. 0 8. 0 0. 25 10% M.W. 2,000,000 1: (100 -z) 70:3 2. 1 7. 9 0. 26 10% N.W.1,300,000 x: 100.1.

70:30 2.1 8.2 0.25 16% MW. 700,000 :r: (100-1) 70:30.. 2. 4 8. 5 0. 28

Increase of 15-30% of D /amount of silver was recognized by adding the acrylamide-acrylic acid copolymers of the present invention.

EXAMPLE 3 The same procedure as in the above-mentioned example was carried out but using acrylamide-methacrylic acid copolymer (M.W. approximately 100,000 x:(l00-x=50:50), methacrylamide acrylic copolymer (M.W. approximately 100,000 x:(l00-x)=30:70), methacrylamide-methacrylic acid copolymer (M.W. approximately 100,000 x:(l00-x)=30:70) and acrylarnideethyl methacrylate copolymer (M.W. approximately 100,000 x:(100-x) =70230).

The resulting data are shown in Table 3.

TABLE 3 Increase of 1625% of D /amount of silver was recognized by addition of the copolymers of the present invention.

EXAMPLE 4 Cyan color development was carried out (at 27 C. for 5 minutes) instead of the development by the magenta developing solution in the developing treatment of the emulsion layer in Example 2. Similarly, yellow color development was carried out (at 27 C. for 5 minutes) instead of the magneta development. The resulting data are shown in the following Table 4 and Table 5.

Formulations of the cyan color developer and the yellow color developer used are as follows.

Cyan color developer:

Potassium bromide g 20 0.1% potassium iodide cc 20 Potassium thiocyanate g 3.0 Anhydrous sodium sulfite g 10 Sodium carbonate (monohydrate) g 30 Sodium hydroxide g 2.0 S-nitrobenzimidazolone nitrate g 0.5 2,4-dichloro-1-naphthol -g 2.0 4 amino-3-methyl-N,N'-diethylaniline hydrochloride g 3.0 Water to make litre 1 Yellow color developing solution:

Sodium sulfite g 5.0 N,N'-diethyl-paraphenylenediamine g 1.2 Sodium carbonate (monohydrate) g 20.0 Potassium bromide g 0.3 0.1% potassium iodide -cc 20 Z-benzoyl-(4'paratoluenesulfonamide) acetanilide g 1.0 Sodium hydroxide g 4.0 Water to make litre 1 TABLE 4 Silver developed Ratio of polymer in binder of by color Cyan gelatin polymer mixture (percent Cyan developer, Dmm/ y w ght) m. mg. Ag/10 cm. silver 0 1.2 8.2 0. 15 16% polyacryla e (M 3,000 00 1.5 0. 0 0.17 16% polyacrylamide (M.W.

TABLE 5 Silver developed Ratio of polymer in hinder or by color Yellow gelatin polymer mixture (percent Yellow developer, Dumb] by weight) muxmg. Ag/lO cm silver 1.5 8.9 0.17 16% polyacrylamide (M W Increase of D /amount of silver was recognized similarly at cyan development and yellow development.

What is claimed is:

1. In a photographic reversal color process, wherein a photographic element containing three photographic silver halide emulsion layers is subjected to:

(1) a first exposure to produce a latent image therein,

(2) development in a photographic developer for producing a black-and-White negative image.

(3) exposure to light of a color to which said first exposed silver halide emulsion layer is sensitive, and

(4) a second development in a color developer for producing a colored image,

said color developer containing an aromatic primary amine color developing agent and a photographic color coupler selected from the group consisting of a magenta forming pyrazolone color coupler, a cyan forming phenolic coupler, and a yellow forming open chain kctomethylene color coupler, the improvement which comprises:

providing a binder for said silver halide consisting essentially of a gelatin and a water-soluble copolymer exhibiting a molecular weight ranging from 5,000 to 3,000,000, characterized as containing as a repeating unit within said copolymer, a structure of the following formula:

2. The process of claim 1, wherein said copolymer is an acrylamide-acrylic acid copolymer.

3. The process of claim 1, wherein said copolymer is an acrylamide-methacrylic acid copolymer.

4. The process of claim 1, wherein said copolymer is a methacrylamide-acrylic acid copolymer.

5. The process of claim 1, wherein said copolymer is a methacrylamide-methacrylic acid copolymer.

6. The process of claim 1, wherein said copolymer is a methacrylamide-ethyl methacrylate copolymer.

7. The process of claim 1, wherein said copolymer is present in an amount ranging from 1 to 90%. by weight, based on the combined weight amount of said gelatin and said copolymer.

8. The process of claim 1, wherein said copolymer is present in an amount ranging from 5 to 50% by weight, based on the combined weight amount of said gelatin and said copolymer.

References Cited UNITED STATES PATENTS 3,592,215 8/1971 Abel, et al. 96-114 RONALD H. SMITH, Primary Examiner A. T. SURO PICO, Assistant Examiner US. Cl. X.R. 961 14 

